开云体育

Cans of worms often need opening... If only to let in
some daylight.

I started a thread earlier about the same subject, but
didn't get much help on settings.

What I have found is if the AGC threshold is set below,
or near, the background noise S-value, the AGC will modulate
the CW note with a clipped version of the noise. I believe
it has something to do with switching an attenuator in and
out at the noise rate... But, I am not sure.

What I do, is observe the noise's S level (count the bars,
and it is 3db per bar) and set the threshold about 1 S unit
higher.

There is a whole slew of settings that should be done by the
band, including AGC, and USB/LSB, volume... but that doesn't
seem to have been done, yet.

So, your high noise AGC settings for 160M will have to be
reset whenever you change to a lower noise band.

Some tuning hints "from on high" would be helpful, if Hans
ever has the time, and is so inclined.

-Chuck Harris - WA3UQV


On Sat, 4 Jan 2025 19:06:38 -0800 "Jay W6CJ via groups.io"
<lastradioman@...> wrote:

Group-
Hope this does not open a whole can of worms, but what are some
good-sounding AGC settings for CW ops? I'm in a high-QRN area.
Thanks & 72
Jay
W6CJ

Good AGC settings (italics=default): AGC ON, Threshold 8 or 9, Slope dB/dB 40-80, Noise Filter 5-10, Hang time 30-80, Smooth 50, Recovery dB/s 10-50, Sample Blocks 2 (CW) - 5 (other modes), S9 sounds like S 9, AGC display OFF, AGC db/Bar 3 or 6,

Reduce CW clicks: Sidetone relative, AGC off

I thought the whole point of using SDR's was to eliminate
most of the difference between examples of a given radio.

W1AW works perfectly with just about any AGC setting here
at my location... mostly because it is something like 20
over S9 most all the time.

Where I have serious difficulty is when signals are one bar
or lower and aren't even making the AGC bar show up on the
LCD display.

In those cases, the noise on the band modulates, in a scratchy
fuzz box sort of way the tone of the otherwise clear signal.

If, however, I turn off the AGC, or I tune in the signal in the
DIGI mode, the scratchy modulation goes away.

It seems to me that having the AGC below the ambient noise level
has something to do with the scratchy modulation.

I am currently playing with:

AGC: ON
Threshold S: 12
Slope dB per dB: 80
Noise Filter: 10
Hang Time: 80
Smooth Samples: 50
Recovery dB/s: 10
Sample Blocks: 2
S9 sounds like S9
AGC Display: ON
AGC dB per Bar: 3

It is not clear to me which of the above settings would be most
likely to remove the scratchy modulation of the received CW tone.

-Chuck Harris - WA3UQV

On Mon, 06 Jan 2025 04:46:43 -0800 "Daniel Conklin via groups.io"
<danconklin2@...> wrote:

Really, it depends on you and your ears, and the differences from
radio to radio. Things are not all going to be equal. The default
settings were chosen because they are a good starting point. That
advice about adjusting settings while listening to W1AW on a good day
is good advice. -- 73, Dan - W2DLC

Since the AGC settings seem to be very dependent on the
ambient noise on the band, it would be helpful for me to
know on which band the settings are optimal, and what
level the ambient noise is when they are working best.

-Chuck Harris, WA3UQV


On Mon, 06 Jan 2025 07:01:45 -0800 "Mike, KL7MJ via groups.io"
<alaskamike@...> wrote:

Steve -
I was actually rereading the posts last week, and I adjusted my
settings to be somewhat the same as yours. Here's what I compiled
from a couple of threads - I apologize for not accrediting a couple
of the settings very well.

QMX Manual G4EDG Ron Other K7VIQ KL7MJ Threshold 8 4 7 7 8 4 Slope 80
50 95 60 80 80 Noise 10 0 5 5 10 10 Hang 80 2 50 30 80 30 Smooth 50 0
99 50 50 50 Recovery 10 60 40 50 10 10 Sample 5 2 4 4 2 2 S9 S9 S9 S9
S9 S0 S6 AGC display ON ON ON ON ON ON AGC dB per bar 3 3 3 3 3 3

73,
Mike, KL7MJ

Dan,

I am a retired EE, and easily 50 years a ham. I know
about band conditions, have experienced a lot of different
receivers, and through the conscientious use of PPE, have
ears that still work properly.

I spent most of my career designing hardware and software
for embedded systems, and in the course of so doing, wrote
tons and tons of "C" and assembler code.

I "get" the signal path of SDR's, and I don't think my situation
has anything to do with hardware, or my ears.

What we are talking about, is 40m on a day when the ambient
noise level was 1 to 1.5 bars, when something happened that
caused every signal on the band to have its audio tone hard
clipped by what sounded like random noise.

Initially, I thought it was some overdriven CW transmitters...
But it was way too many.

This situation only happened when the AGC was turned on, and
only in CW mode. Everything was clean and pure in the USB DIGI
mode.

I was using the factory default AGC settings, and I think
the latest release of software.

That sounds like an AGC issue to me, and there is no AGC
hardware in this radio, at all, so a software AGC problem.

I don't believe that my radio, or my situation is unique,
so, perhaps my report will trigger someone to actually look
for, and apply a fix.

Since there is absolutely nothing I can do to fix software
problems in my radio, I am hoping for band-aid solutions in
the AGC settings section.

Thus far, the only thing that seems to help is to all but
disable the AGC by putting the threshold up to 12. That seems
quite counter to those suggesting settings of 3 or 4, which
caused me to ask: for what band?

OBTW, since some of the members of this group seem to be on
Hans' team, would it be too much to ask that they identify
themselves as such somehow in their posts?

-Chuck Harris, WA3UQV

On Mon, 06 Jan 2025 08:30:26 -0800 "Daniel Conklin via groups.io"
<danconklin2@...> wrote:

Chuck,
Regardless of software definition or not, the hardware will have
variations, and your ears will have variations, and band conditions
will vary. Your AGC will respond to those variables digitally but
converted to an analog way because ultimately, the output is analog
to your ears. I have one ear that's a lot more sensitive than the
other. Certain loud sounds can get buzzy and distorted to that ear.
The other ear has had damage due to unprotected exposure to very loud
sounds over time, so certain parts of the audio spectrum are muted.
The interaction between the CW filters and the AGC settings can
compensate for some of that, but not all of it. Part of the reason
for the default settings was to help compensate for a thumping sound
some were getting when keying.? I never even perceived that thump
with either of my QMXs. I don't think I have that thump because it's
not there in either ear. You are having with some pulsing at low
levels. I haven't noticed that in any situation I've
experienced...yet. Maybe I will, now that you've called my attention
to it. Also, remember that Hans made you check a box stating you
understand this is Beta software, so you knew what you were getting
into. I know he makes a note of every complaint, and has it in mind
as he works on the firmware, so he will probably try to reproduce
your observation eventually. Anyway, I'm happy with my settings which
most of the time are:

Threshold S: 8
Slope dB per dB: 65
Noise Filter: 9
Hang time: 55
Smooth samples: 60
Recovery dB/s: 8
Sample Blocks: 2
S9 sounds like: S9
AGC Display: On
AGC dB per Bar: 3

But, I'm also still experimenting.
--
73, Dan - W2DLC

Hi Hans,

Thank you for your reply.

Initially I tried both lower and higher AGC thresholds, and
found they did not help the situation. OFF seemed to do the
best at eliminating the noise modulation of the CW tones.

OFF isn't my idea of a good way to operate as I would like to
preserve my hearing.

You might note that there are now others reporting the same
problem.

My SWAG on the problem is that the AGC routine's inputs
are from before the CW filters, and the AGC routines outputs
affect the audio levels after the CW filters.

Something is causing the AGC to modulate the CW notes with
noise that otherwise isn't within the CW filters bandwidth.

How do I know this? The noise is too sibilant and crackly
to have passed through a narrow CW filter.

But I am operating entirely in the blind about what your
software does, so this is just the ramblings of a retired EE.

I could not help but notice that many on this group speak
possessively about this product, as if they had something to
do with its creation.

I could not help but notice that many on this group beat their
chests threateningly and point out reasons why I should shut
my mouth.

Perhaps it is simply pride because you acted on one or more of
their suggestions?

I meant no disrespect. My feeling was that if others are
speaking on your behalf, I should like to know so I can treat
their opinions as being more informed.

-Chuck Harris, WA3UQV


On Wed, 8 Jan 2025 11:56:48 +0300 "Hans Summers via groups.io"
<hans.summers@...> wrote:

Hello Chuck

Since there is absolutely nothing I can do to fix software

problems in my radio, I am hoping for band-aid solutions in
the AGC settings section.

Have you tried some of the settings people suggested in this forum?

OBTW, since some of the members of this group seem to be on
Hans' team, would it be too much to ask that they identify
themselves as such somehow in their posts?

I am not sure who you think is on the group who is on my team but I
definitely assure you, no QRP Labs team (either employees or less
official) are active on this forum other than me.

73 Hans G0UPL

Hi Hans,

No, I did not try the other settings.

I have read over the descriptions of what they do, and
not knowing the architecture, I can't relate the settings
to the problem I am seeing.

I'm an engineer, whacking at problems randomly is rarely
productive.

When the AGC is exposed to nothing but strong signals,
like W1AW, it is by far the best I have ever used.

When the AGC is exposed to high ambient noise outside of
the CW filter's bandwidth, the audio produces sounds that
simply cannot come out of a properly functioning CW filter.

Sibilance and cracky sounds have high frequency components
out to the 9th harmonic and beyond. They shouldn't be
coming out of a CW filter.

They audio levels seem too low to have driven any of the
audio hardware into clipping. Much higher levels haven't.

I too am enthusiastic about this product, so I understand
the excitement it brings.

But, being reminded that I checked a box when I made my
purchase acknowledging this is a Beta release, as if that
makes my questions unreasonable, feels like something else.

I don't want to see your effort "knee-capped" by fixable
problems you don't know about.

-Chuck Harris, WA3UQV


On Thu, 9 Jan 2025 12:38:11 +0300 "Hans Summers via groups.io"
<hans.summers@...> wrote:

Hello Chuck

Initially I tried both lower and higher AGC thresholds, and
found they did not help the situation. OFF seemed to do the
best at eliminating the noise modulation of the CW tones.

Did you try changing the other parameters other than AGC threshold?

I will look into it again when I have a chance; it has been a while
since the AGC functionality was added and I get the impression
generally most people think it is working well.

I think that there are settings which could cause it to be scratchy.

I do intend to create some "known good" settings to choose from to
make it easy; leave the extensive full configurability in there for
people who want it, but a few easy settings.

My SWAG on the problem is that the AGC routine's inputs
are from before the CW filters, and the AGC routines outputs
affect the audio levels after the CW filters.

Something is causing the AGC to modulate the CW notes with
noise that otherwise isn't within the CW filters bandwidth.

How do I know this? The noise is too sibilant and crackly
to have passed through a narrow CW filter.

The AGC action takes place AFTER the CW filter. If the crackling was
generated by AGC that was ahead of the CW filter then the crackling
would be filtered out by the CW filter...

I could not help but notice that many on this group speak
possessively about this product, as if they had something to
do with its creation.

I could not help but notice that many on this group beat their
chests threateningly and point out reasons why I should shut
my mouth.

Perhaps it is simply pride because you acted on one or more of
their suggestions?

Just enthusiasm, I suspect; most people here have had a lot of fun
with the QRP Labs products. I am reading most of the posts here, I
had not noticed people beating chests threateningly in regard to your
questions.

I meant no disrespect. My feeling was that if others are
speaking on your behalf, I should like to know so I can treat
their opinions as being more informed.

No problem :-) Nobody speaks on my behalf.

73 Hans G0UPL

Hi Stan,

Every setting is default other than the threshold.

The smooth samples setting is 50.

-Chuck Harris, WA3UQV


On Fri, 10 Jan 2025 15:15:50 -0800 "Stan Dye via groups.io"
<standye@...> wrote:

Hans,
In the 2nd-to-last paragraph of your QMX AGC description (just before
describing the available settings), it seems like you have already
described this 'scratchy sound' issue, and provided a parameter
"smooth samples" to correct for it.? Is this the same thing?? Or are
we talking about something different?

Chuck,
Please check your "smooth samples" AGC setting, and make sure it is
not set to 0 or another low value.? It probably should be around 50,
and can't go above 64 (assuming your "sample blocks" is at the
recommended value of 2).

Stan KC7XE